Packages
library(DT)
library(adabag)
library(rpart.plot)
library(pROC)
library(summarytools)
library(corrplot)
library(dplyr)
library(GGally)
library(fastDummies)
library(ggcorrplot)
library(klaR)
library(psych)
library(MASS)
library(devtools)
library(ggplot2)
library(ggthemes)
library(GGally)
library(caret)
library(splitTools)
library(rpart)
library(xgboost)
library(caTools)
library(dplyr)
library(caret)
library(naniar)
library(kableExtra)
CM_Function <- function(cm) {
layout(matrix(c(1,1,2)))
par(mar=c(2,2,2,2))
plot(c(100, 345), c(300, 450), type = "n", xlab="", ylab="", xaxt='n', yaxt='n')
title('CONFUSION MATRIX', cex.main=2)
# create the matrix
rect(150, 430, 240, 370, col='#2F4F4E')
text(195, 435, 'No', cex=1.2)
rect(250, 430, 340, 370, col='#0D8387')
text(295, 435, 'Yes', cex=1.2)
text(125, 370, 'Predicted', cex=1.3, srt=90, font=2)
text(245, 450, 'Actual', cex=1.3, font=2)
rect(150, 305, 240, 365, col='#0D8387')
rect(250, 305, 340, 365, col='#2F4F4E')
text(140, 400, 'No', cex=1.2, srt=90)
text(140, 335, 'Yes', cex=1.2, srt=90)
# add in the cm results
res <- as.numeric(cm$table)
text(195, 400, res[1], cex=1.6, font=2, col='white')
text(195, 335, res[2], cex=1.6, font=2, col='white')
text(295, 400, res[3], cex=1.6, font=2, col='white')
text(295, 335, res[4], cex=1.6, font=2, col='white')
# add in the specifics
plot(c(100, 0), c(100, 0), type = "n", xlab="", ylab="", main = "DETAILS", xaxt='n', yaxt='n')
text(10, 85, names(cm$byClass[1]), cex=1.2, font=2)
text(10, 70, round(as.numeric(cm$byClass[1]), 3), cex=1.2)
text(30, 85, names(cm$byClass[2]), cex=1.2, font=2)
text(30, 70, round(as.numeric(cm$byClass[2]), 3), cex=1.2)
text(50, 85, names(cm$byClass[5]), cex=1.2, font=2)
text(50, 70, round(as.numeric(cm$byClass[5]), 3), cex=1.2)
text(70, 85, names(cm$byClass[6]), cex=1.2, font=2)
text(70, 70, round(as.numeric(cm$byClass[6]), 3), cex=1.2)
text(90, 85, names(cm$byClass[7]), cex=1.2, font=2)
text(90, 70, round(as.numeric(cm$byClass[7]), 3), cex=1.2)
# add in the accuracy information
text(30, 35, names(cm$overall[1]), cex=1.5, font=2)
text(30, 20, round(as.numeric(cm$overall[1]), 3), cex=1.4)
text(70, 35, names(cm$overall[2]), cex=1.5, font=2)
text(70, 20, round(as.numeric(cm$overall[2]), 3), cex=1.4)
}
DATA AND QUICK FACTORING
df <- readxl::read_xls('Cchurn.xls')
df$international_plan <- factor(df$international_plan, levels = c('no', 'yes'), labels = c('0','1'))
df$voice_mail_plan <- factor(df$voice_mail_plan, levels = c('no', 'yes'), labels = c('0','1'))
df$churn <- factor(df$churn, levels = c('no', 'yes'), labels = c('0','1'))
SUMMARY
print(summarytools::dfSummary(df), method = 'render')
- We have no missing values -> perfect
- Heavily uneven counts of dependent variable (86 % no / 14 % yes)
-> maybe sample for equality / maybe not because we loose information
of other data
- Independent variables are on different scales -> standardize
- two (maybe three) categorical predictors: International plan /
voice_mail_plan (/ maybe number_customer_service_calls) -> dummy
encode -> not necessary as already 0 and 1
- Rest of data is numeric and most of the variables looks normally
distributed with exception of number_vmail_messages and totat_intl_calls
- transform these value to make them normal?
- maybe make parts of them categorical? (recieving voice mail or not,
calling internationally or not)
- or maybe the categorical values that we have already give an
indication for this
- Test normality of variables
- Can variables be combined? We have day / eve / night / intl calls
and for each of them minutes / calls / charge. Maybe we can combine this
into one metric. Maybe average cost per minute or average cost per
call?
CORRELATION PLOT BEFORE DATA ENGINEERING
df_numeric <- select_if(df, is.numeric) # Subset numeric columns with dplyr
M <- cor(df_numeric)
p.mat <- cor_pmat(df_numeric)
ggcorrplot(M, hc.order = TRUE, type = "lower", lab = TRUE, p.mat = p.mat, sig.level=0.05, lab_size = 2, tl.cex = 10,outline.col = "white", ggtheme = ggplot2::theme_minimal(), colors = c("#2F4F4E", "white", "#0D8387"))

Proves theory from before -> we can make one metric out of charge
and minutes –> charge / minutes
DATA ENGINEERING
df$total_day_charge_per_minute <- ifelse(df$total_day_minutes == 0, 0, df$total_day_charge / df$total_day_minutes)
df$total_eve_charge_per_minute <- ifelse(df$total_eve_minutes == 0, 0, df$total_eve_charge / df$total_eve_minutes)
df$total_night_charge_per_minute <- ifelse(df$total_night_minutes == 0, 0, df$total_night_charge / df$total_night_minutes)
df$total_intl_charge_per_minute <- ifelse(df$total_intl_minutes == 0, 0, df$total_intl_charge / df$total_intl_minutes)
df <- subset(df, select = -c(total_day_charge, total_day_minutes, total_eve_charge, total_eve_minutes, total_night_charge, total_night_minutes, total_intl_charge, total_intl_minutes))
CORRELATION PLOT AFTER DATA ENGINEERING
df_numeric <- select_if(df, is.numeric) # Subset numeric columns with dplyr
M <- cor(df_numeric)
p.mat <- cor_pmat(df_numeric)
ggcorrplot(M, hc.order = TRUE, type = "lower", lab = TRUE, p.mat = p.mat, sig.level=0.05, lab_size = 2, tl.cex = 10,outline.col = "white", ggtheme = ggplot2::theme_minimal(), colors = c("#2F4F4E", "white", "#0D8387"))

Now we have non-correlated data
HIGHER ORDER FEATURES
Only squaring as we have no negative data. Cubing would be needed
with negative data.
# squared
df2 <- df^2
df2 <- df2[,-c(2,3,10)]
colnames(df2) <- paste0(colnames(df2), '_sqd')
df <- cbind(df,df2)
Relationship between data in higher order
# theme_set(theme_minimal())
#
# ggpairs(
# data = df,
# columns = c(1:9, 11:25),
# mapping = aes(col = churn, alpha = .9)
# ) +
# scale_fill_colorblind() +
# scale_color_colorblind()
SAMPLING METHODS
As we have unbalanced data we need to use a sampling method to
balance the classes. Hereby there are four different methods. OVER /
UNDER / BOTH / ROSE.
library(ROSE)
# OVER
df_OVER <- ovun.sample(churn~., data = df, method = "over")$data
table(df$churn)
FALSE
FALSE 0 1
FALSE 4293 707
table(df_OVER$churn)
FALSE
FALSE 0 1
FALSE 4293 4244
# UNDER
df_UNDER <- ovun.sample(churn~., data = df, method = "under")$data
table(df$churn)
FALSE
FALSE 0 1
FALSE 4293 707
table(df_UNDER$churn)
FALSE
FALSE 0 1
FALSE 722 707
# BOTH
df_BOTH <- ovun.sample(churn~., data = df, method = "both")$data
table(df$churn)
FALSE
FALSE 0 1
FALSE 4293 707
table(df_BOTH$churn)
FALSE
FALSE 0 1
FALSE 2561 2439
# ROSE
df_ROSE <- ROSE(churn ~ ., data = df, seed = 1, p = 0.5)$data
SAMPLING POST VISUALIZATION
# theme_set(theme_minimal())
#
# ggpairs(
# data = df_ROSE,
# columns = c(1:9, 11:25),
# mapping = aes(col = churn, alpha = .9)
# ) +
# scale_fill_colorblind() +
# scale_color_colorblind() +
# labs(title = "Machine Learning Project")
#
# ggpairs(
# data = df_OVER,
# columns = c(1:9, 11:25),
# mapping = aes(col = churn, alpha = .9)
# ) +
# scale_fill_colorblind() +
# scale_color_colorblind() +
# labs(title = "Machine Learning Project")
# ggpairs(
# data = df_UNDER,
# columns = c(1:9, 11:25),
# mapping = aes(col = churn, alpha = .9)
# ) +
# scale_fill_colorblind() +
# scale_color_colorblind() +
# labs(title = "Machine Learning Project")
# ggpairs(
# data = df_BOTH,
# columns = c(1:9, 11:25),
# mapping = aes(col = churn, alpha = .9)
# ) +
# scale_fill_colorblind() +
# scale_color_colorblind() +
# labs(title = "Machine Learning Project")
TRAIN AND TEST SPLIT
As we need to test the models we need to split the sampled data.
set.seed(1)
data <- df_OVER # choose which data to use df_ROSE / df_BOTH / df_UNDER / df_OVER / df
inds <- splitTools::partition(data$churn, p = c(train = 0.7, test = 0.3))
dftrain <- data[inds$train,]
dftest <- data[inds$test,]
SCALING
As some methods need scaled data we scale the data here to be
centered.
norm.value <- preProcess(dftrain, method = c("center", "scale"))
dftrain <- predict(norm.value, dftrain)
dftest <- predict(norm.value, dftest)
df_original_test <- predict(norm.value, df)
PREDICTIVE MODELS
BOOSTING
set.seed(123)
# train bagged model
mod.boost <- boosting(churn ~., data=dftrain)
predicted.boost <- factor(predict(mod.boost, dftest, type="class")$class)
PRED_BOOSTING <- predicted.boost
confmat.boost <- confusionMatrix(data=predicted.boost, reference = dftest$churn, positive = '1')
CM_Function(confmat.boost)

roc_score.boost =roc(factor(dftest$churn, ordered=TRUE), factor(predicted.boost, ordered=TRUE))
plot(roc_score.boost ,main ="ROC curve")

BOOSTING ON ORIGINAL DATA
predicted.boost <- factor(predict(mod.boost, df_original_test, type="class")$class)
PRED_BOOSTING_ORIGINAL <- predicted.boost
confmat.boost <- confusionMatrix(data=predicted.boost, reference = df_original_test$churn, positive = '1')
CM_Function(confmat.boost)

roc_score.boost =roc(factor(df_original_test$churn, ordered=TRUE), factor(predicted.boost, ordered=TRUE))
plot(roc_score.boost ,main ="ROC curve")

CTREE
set.seed(123)
tree_full <- rpart(churn ~ .,
data = dftrain,
method = "class", # "class" because Y is a binary factor
minbucket = 1,
cp = 0.00001)
# Plot tree
rpart.plot(tree_full, yesno = TRUE, digits =-6)

min_xerr<- which.min(tree_full$cptable[,"xerror"]) # select minimum cross-validation error
cp_bp <- tree_full$cptable[min_xerr,"CP"] # find the corresponding CP value, to get the "best pruned " tree
mod.pruned_tree<- prune(tree_full, cp = cp_bp) # re-compute the tree with the selected Cp
rpart.plot(mod.pruned_tree, yesno = TRUE, digits =-3)

predicted.pruned_tree <- predict(mod.pruned_tree, dftest[,-c(10)], type = "class")
PRED_CTREE <- predicted.pruned_tree
confmat.prunned_tree <- confusionMatrix(data=predicted.pruned_tree, reference = dftest$churn, positive = '1')
CM_Function(confmat.prunned_tree)

roc_score.prunned_tree =roc(factor(dftest$churn, ordered=TRUE), factor(predicted.pruned_tree, ordered=TRUE))
plot(roc_score.prunned_tree ,main ="ROC curve")

library(rattle)
rpart.plot(mod.pruned_tree, yesno = TRUE, digits =-3)

# Customizing the output
pdf("CTREE.pdf",
width = 30, height = 30,
bg = "white",
colormodel = "rgb")
# Creating a plot
fancyRpartPlot(mod.pruned_tree,yesno=TRUE,main="Pruned Tree",tweak=3)
# Closing the graphical device
dev.off()
FALSE quartz_off_screen
FALSE 2
CTREE ON ORIGINAL DATA
predicted.pruned_tree <- predict(mod.pruned_tree, df_original_test[,-c(10)], type = "class")
PRED_CTREE_ORIGINAL <- predicted.pruned_tree
confmat.prunned_tree <- confusionMatrix(data=predicted.pruned_tree, reference = df_original_test$churn, positive = '1')
CM_Function(confmat.prunned_tree)

roc_score.prunned_tree =roc(factor(df_original_test$churn, ordered=TRUE), factor(predicted.pruned_tree, ordered=TRUE))
plot(roc_score.prunned_tree ,main ="ROC curve")

VARIABLES IMPORTANCES
relevance<-as.data.frame(mod.pruned_tree$variable.importance) #we get the ranking of the variables by importance
kable(relevance, row.names = T,col.names="Variable Importance") %>% kable_paper("hover", full_width = T) #built table
|
|
Variable Importance
|
|
total_day_charge_per_minute
|
557.2676
|
|
total_day_charge_per_minute_sqd
|
476.0339
|
|
account_length
|
469.8823
|
|
number_customer_service_calls
|
449.8173
|
|
number_customer_service_calls_sqd
|
422.7798
|
|
total_eve_charge_per_minute
|
403.5980
|
|
total_day_calls
|
375.5245
|
|
total_night_calls
|
364.1848
|
|
account_length_sqd
|
340.9402
|
|
total_eve_calls
|
337.1126
|
|
total_intl_charge_per_minute
|
329.5445
|
|
international_plan
|
311.4832
|
|
total_eve_charge_per_minute_sqd
|
311.4364
|
|
total_intl_calls
|
306.5993
|
|
total_night_charge_per_minute
|
297.4428
|
|
total_intl_charge_per_minute_sqd
|
279.6778
|
|
total_day_calls_sqd
|
275.8987
|
|
total_night_calls_sqd
|
273.6340
|
|
total_eve_calls_sqd
|
258.6304
|
|
total_night_charge_per_minute_sqd
|
243.1360
|
|
total_intl_calls_sqd
|
236.3298
|
|
number_vmail_messages
|
197.4317
|
|
number_vmail_messages_sqd
|
180.8030
|
|
voice_mail_plan
|
121.0192
|
relevance
FALSE mod.pruned_tree$variable.importance
FALSE total_day_charge_per_minute 557.2676
FALSE total_day_charge_per_minute_sqd 476.0339
FALSE account_length 469.8823
FALSE number_customer_service_calls 449.8173
FALSE number_customer_service_calls_sqd 422.7798
FALSE total_eve_charge_per_minute 403.5980
FALSE total_day_calls 375.5245
FALSE total_night_calls 364.1848
FALSE account_length_sqd 340.9402
FALSE total_eve_calls 337.1126
FALSE total_intl_charge_per_minute 329.5445
FALSE international_plan 311.4832
FALSE total_eve_charge_per_minute_sqd 311.4364
FALSE total_intl_calls 306.5993
FALSE total_night_charge_per_minute 297.4428
FALSE total_intl_charge_per_minute_sqd 279.6778
FALSE total_day_calls_sqd 275.8987
FALSE total_night_calls_sqd 273.6340
FALSE total_eve_calls_sqd 258.6304
FALSE total_night_charge_per_minute_sqd 243.1360
FALSE total_intl_calls_sqd 236.3298
FALSE number_vmail_messages 197.4317
FALSE number_vmail_messages_sqd 180.8030
FALSE voice_mail_plan 121.0192
BAGGING
set.seed(123)
library(ipred)
library(pROC)
# train bagged model
ames_bag1 <- bagging(
formula = churn ~ .,
data = dftrain,
nbagg = 100,
coob = TRUE,
control = rpart.control(minsplit = 2, cp = 0)
)
ames_bag1
FALSE
FALSE Bagging classification trees with 100 bootstrap replications
FALSE
FALSE Call: bagging.data.frame(formula = churn ~ ., data = dftrain, nbagg = 100,
FALSE coob = TRUE, control = rpart.control(minsplit = 2, cp = 0))
FALSE
FALSE Out-of-bag estimate of misclassification error: 0.0418
predicted <- factor(ifelse(predict(ames_bag1, dftest[,-c(10)], type = 'prob')[,2] >= 0.5, 1, 0))
PRED_BAGGING <- predicted
CM_Function(confusionMatrix(data=predicted, reference = dftest$churn, positive = '1'))

roc_score=roc(factor(dftest$churn, ordered=TRUE), factor(predicted, ordered=TRUE)) #AUC score
auc <- round(auc(factor(dftest$churn, ordered=TRUE), factor(predicted, ordered=TRUE)),4)
ggroc(roc_score, colour = '#0D8387', size = 1) +
ggtitle(paste0('ROC Curve ', '(AUC = ', auc, ')')) + theme_minimal() + theme(plot.title = element_text(face = "bold")) + labs(x="Specificity", y="Sensitivity")

BAGGING ON ORIGINAL DATA
predicted <- factor(ifelse(predict(ames_bag1, df_original_test[,-c(10)], type = 'prob')[,2] >= 0.5, 1, 0))
PRED_BAGGING_ORIGINAL <- predicted
CM_Function(confusionMatrix(data=predicted, reference = df_original_test$churn, positive = '1'))

roc_score=roc(factor(df_original_test$churn, ordered=TRUE), factor(predicted, ordered=TRUE)) #AUC score
auc <- round(auc(factor(df_original_test$churn, ordered=TRUE), factor(predicted, ordered=TRUE)),4)
ggroc(roc_score, colour = '#0D8387', size = 1) +
ggtitle(paste0('ROC Curve ', '(AUC = ', auc, ')')) + theme_minimal() + theme(plot.title = element_text(face = "bold")) + labs(x="Specificity", y="Sensitivity")

KNN
set.seed(1)
df <- data.frame(k = seq(1, 30, 1), accuracy = rep(0, 30), sensitivity = rep(0, 30))
# iterating over different ks
for(i in 1:30){
# nearest neighbor
KNN1 <- knn3(y = dftrain$churn, x = dftrain[,-c(10)], k = i)
# predictions response
KNN1.pred.valid.resp <- predict(KNN1, dftest[,-c(10)], type = "class")
# predictions prob
KNN1.pred.valid.prob <- predict(KNN1, dftest[,-c(10)], type = "prob")[,2]
# Confusionmatrix
df$sensitivity[i] <- confusionMatrix(KNN1.pred.valid.resp, dftest$churn, positive = "1")$byClass[1]
df$accuracy[i] <- confusionMatrix(KNN1.pred.valid.resp, dftest$churn, positive = "1")$overall[1]
}
# plot the k's
ggplot(df, aes(x=k)) +
geom_line(aes(y = sensitivity, colour = "Sensitivity")) +
geom_line(aes(y = accuracy, colour = "Accuracy")) +
labs(x = "Number of k nearest neighbours",
y = "Accuracy / Sensitivity", title = "Accuracy / Sensitivity regarding k") +
theme_minimal() +
scale_y_continuous(name = "Sensitivity / Accuracy", limits = c(0.7, 1)) +
scale_color_manual(name = "Values", values = c("Sensitivity" = "darkblue", "Accuracy" = "red")) +
xlim (1, 30)

mod.knn <- knn3(y = dftrain$churn, x = dftrain[,-c(10)], k = 2)
predicted.knn <- predict(mod.knn, dftest[,-c(10)], type = "class")
PRED_KNN <- predicted.knn
confmat.knn <- confusionMatrix(data=predicted.knn, reference = dftest$churn, positive = '1')
CM_Function(confmat.knn)

roc_score.qda =roc(factor(dftest$churn, ordered=TRUE), factor(predicted.knn, ordered=TRUE))
plot(roc_score.qda ,main ="ROC curve")

KNN ON ORIGINAL DATA
predicted.knn <- predict(mod.knn, df_original_test[,-c(10)], type = "class")
PRED_KNN_ORIGINAL <- predicted.knn
confmat.knn <- confusionMatrix(data=predicted.knn, reference = df_original_test$churn, positive = '1')
CM_Function(confmat.knn)

roc_score.qda =roc(factor(df_original_test$churn, ordered=TRUE), factor(predicted.knn, ordered=TRUE))
plot(roc_score.qda ,main ="ROC curve")

QDA
mod.qda <- qda(churn ~., data = dftrain)
predicted.qda <- predict(mod.qda, dftest[,-c(10)])$class
confmat.qda <- confusionMatrix(data=predicted.qda, reference = dftest$churn, positive = '1')
CM_Function(confmat.qda)

roc_score.qda =roc(factor(dftest$churn, ordered=TRUE), factor(predicted.qda, ordered=TRUE))
plot(roc_score.qda ,main ="ROC curve")

QDA ON ORIGINAL DATA
predicted.qda <- predict(mod.qda, df_original_test[,-c(10)])$class
confmat.qda <- confusionMatrix(data=predicted.qda, reference = df_original_test$churn, positive = '1')
CM_Function(confmat.qda)

roc_score.qda =roc(factor(df_original_test$churn, ordered=TRUE), factor(predicted.qda, ordered=TRUE))
plot(roc_score.qda ,main ="ROC curve")

QLOG
mod.log <- glm(churn ~., data = dftrain, family = binomial(link = "probit"))
s <- step(mod.log)
FALSE Start: AIC=6774.11
FALSE churn ~ account_length + international_plan + voice_mail_plan +
FALSE number_vmail_messages + total_day_calls + total_eve_calls +
FALSE total_night_calls + total_intl_calls + number_customer_service_calls +
FALSE total_day_charge_per_minute + total_eve_charge_per_minute +
FALSE total_night_charge_per_minute + total_intl_charge_per_minute +
FALSE account_length_sqd + number_vmail_messages_sqd + total_day_calls_sqd +
FALSE total_eve_calls_sqd + total_night_calls_sqd + total_intl_calls_sqd +
FALSE number_customer_service_calls_sqd + total_day_charge_per_minute_sqd +
FALSE total_eve_charge_per_minute_sqd + total_night_charge_per_minute_sqd +
FALSE total_intl_charge_per_minute_sqd
FALSE
FALSE Df Deviance AIC
FALSE - total_day_charge_per_minute 1 6724.1 6772.1
FALSE - total_day_charge_per_minute_sqd 1 6724.2 6772.2
FALSE - total_intl_charge_per_minute 1 6724.4 6772.4
FALSE - total_intl_charge_per_minute_sqd 1 6724.5 6772.5
FALSE <none> 6724.1 6774.1
FALSE - account_length_sqd 1 6726.3 6774.3
FALSE - total_night_calls 1 6726.6 6774.6
FALSE - total_eve_calls 1 6726.9 6774.9
FALSE - total_night_calls_sqd 1 6726.9 6774.9
FALSE - total_eve_calls_sqd 1 6727.2 6775.2
FALSE - total_day_calls 1 6727.4 6775.4
FALSE - account_length 1 6727.6 6775.6
FALSE - total_night_charge_per_minute_sqd 1 6728.3 6776.3
FALSE - total_night_charge_per_minute 1 6728.5 6776.5
FALSE - total_day_calls_sqd 1 6728.5 6776.5
FALSE - number_vmail_messages_sqd 1 6729.9 6777.9
FALSE - number_vmail_messages 1 6732.7 6780.7
FALSE - total_eve_charge_per_minute 1 6744.6 6792.6
FALSE - total_eve_charge_per_minute_sqd 1 6744.6 6792.6
FALSE - number_customer_service_calls 1 6746.1 6794.1
FALSE - total_intl_calls_sqd 1 6746.5 6794.5
FALSE - voice_mail_plan 1 6748.8 6796.8
FALSE - total_intl_calls 1 6754.8 6802.8
FALSE - number_customer_service_calls_sqd 1 6888.9 6936.9
FALSE - international_plan 1 7362.0 7410.0
FALSE
FALSE Step: AIC=6772.15
FALSE churn ~ account_length + international_plan + voice_mail_plan +
FALSE number_vmail_messages + total_day_calls + total_eve_calls +
FALSE total_night_calls + total_intl_calls + number_customer_service_calls +
FALSE total_eve_charge_per_minute + total_night_charge_per_minute +
FALSE total_intl_charge_per_minute + account_length_sqd + number_vmail_messages_sqd +
FALSE total_day_calls_sqd + total_eve_calls_sqd + total_night_calls_sqd +
FALSE total_intl_calls_sqd + number_customer_service_calls_sqd +
FALSE total_day_charge_per_minute_sqd + total_eve_charge_per_minute_sqd +
FALSE total_night_charge_per_minute_sqd + total_intl_charge_per_minute_sqd
FALSE
FALSE Df Deviance AIC
FALSE - total_intl_charge_per_minute 1 6724.5 6770.5
FALSE - total_intl_charge_per_minute_sqd 1 6724.6 6770.6
FALSE <none> 6724.1 6772.1
FALSE - account_length_sqd 1 6726.3 6772.3
FALSE - total_night_calls 1 6726.6 6772.6
FALSE - total_eve_calls 1 6727.0 6773.0
FALSE - total_night_calls_sqd 1 6727.0 6773.0
FALSE - total_eve_calls_sqd 1 6727.2 6773.2
FALSE - total_day_calls 1 6727.5 6773.5
FALSE - account_length 1 6727.6 6773.6
FALSE - total_night_charge_per_minute_sqd 1 6728.3 6774.3
FALSE - total_night_charge_per_minute 1 6728.5 6774.5
FALSE - total_day_calls_sqd 1 6728.5 6774.5
FALSE - number_vmail_messages_sqd 1 6729.9 6775.9
FALSE - number_vmail_messages 1 6732.8 6778.8
FALSE - total_eve_charge_per_minute 1 6744.6 6790.6
FALSE - total_eve_charge_per_minute_sqd 1 6744.6 6790.6
FALSE - total_day_charge_per_minute_sqd 1 6745.2 6791.2
FALSE - number_customer_service_calls 1 6746.1 6792.1
FALSE - total_intl_calls_sqd 1 6746.6 6792.6
FALSE - voice_mail_plan 1 6748.8 6794.8
FALSE - total_intl_calls 1 6754.9 6800.9
FALSE - number_customer_service_calls_sqd 1 6888.9 6934.9
FALSE - international_plan 1 7362.0 7408.0
FALSE
FALSE Step: AIC=6770.47
FALSE churn ~ account_length + international_plan + voice_mail_plan +
FALSE number_vmail_messages + total_day_calls + total_eve_calls +
FALSE total_night_calls + total_intl_calls + number_customer_service_calls +
FALSE total_eve_charge_per_minute + total_night_charge_per_minute +
FALSE account_length_sqd + number_vmail_messages_sqd + total_day_calls_sqd +
FALSE total_eve_calls_sqd + total_night_calls_sqd + total_intl_calls_sqd +
FALSE number_customer_service_calls_sqd + total_day_charge_per_minute_sqd +
FALSE total_eve_charge_per_minute_sqd + total_night_charge_per_minute_sqd +
FALSE total_intl_charge_per_minute_sqd
FALSE
FALSE Df Deviance AIC
FALSE <none> 6724.5 6770.5
FALSE - account_length_sqd 1 6726.7 6770.7
FALSE - total_night_calls 1 6726.9 6770.9
FALSE - total_night_calls_sqd 1 6727.2 6771.2
FALSE - total_eve_calls 1 6727.3 6771.3
FALSE - total_eve_calls_sqd 1 6727.5 6771.5
FALSE - total_day_calls 1 6727.8 6771.8
FALSE - account_length 1 6728.0 6772.0
FALSE - total_night_charge_per_minute_sqd 1 6728.6 6772.6
FALSE - total_night_charge_per_minute 1 6728.8 6772.8
FALSE - total_day_calls_sqd 1 6728.9 6772.9
FALSE - number_vmail_messages_sqd 1 6730.2 6774.2
FALSE - number_vmail_messages 1 6733.0 6777.0
FALSE - total_intl_charge_per_minute_sqd 1 6738.6 6782.6
FALSE - total_eve_charge_per_minute 1 6744.8 6788.8
FALSE - total_eve_charge_per_minute_sqd 1 6744.8 6788.8
FALSE - total_day_charge_per_minute_sqd 1 6745.5 6789.5
FALSE - number_customer_service_calls 1 6746.6 6790.6
FALSE - total_intl_calls_sqd 1 6746.8 6790.8
FALSE - voice_mail_plan 1 6749.0 6793.0
FALSE - total_intl_calls 1 6755.0 6799.0
FALSE - number_customer_service_calls_sqd 1 6889.5 6933.5
FALSE - international_plan 1 7362.1 7406.1
mod.log <- glm(s$formula, data = dftrain, family = binomial(link = "probit"))
predicted.log <- factor(ifelse(predict(mod.log, dftest[,-c(10)], type='response')>0.5,1,0))
confmat.log <- confusionMatrix(data=predicted.log, reference = dftest$churn, positive = '1')
CM_Function(confmat.log)

roc_score.log =roc(factor(dftest$churn, ordered=TRUE), factor(predicted.log, ordered=TRUE))
plot(roc_score.log ,main ="ROC curve")

GAUSSIAN SVM
library(e1071)
mod.svm = svm(formula = churn ~ .,
data = dftrain,
type = 'C-classification', # this is because we want to make a regression classification
kernel = 'radial')
predicted.svm <- predict(mod.svm, dftest[,-c(10)])
confmat.svm <- confusionMatrix(data=predicted.svm, reference = dftest$churn, positive = '1')
CM_Function(confmat.svm)

roc_score.svm =roc(factor(dftest$churn, ordered=TRUE), factor(predicted.svm, ordered=TRUE))
plot(roc_score.svm ,main ="ROC curve")

ENSEMBLES - MAJORITY VOTING
BOOSTING CTREE
BAGGING
ENSEMBLES <- cbind(PRED_BOOSTING,PRED_CTREE,PRED_BAGGING)
ENSEMBLES <- as.data.frame(ENSEMBLES)
ENSEMBLES <- ifelse(ENSEMBLES == 2, 1, 0)
MAJORITY_VOTE <- rep(0,nrow(ENSEMBLES))
MAJORITY_VOTE <- ifelse(rowSums(ENSEMBLES) > (ncol(ENSEMBLES)-1)/2, 1, 0)
ENSEMBLES <- cbind(ENSEMBLES,MAJORITY_VOTE)
ENSEMBLES <- as.data.frame(ENSEMBLES)
ENSEMBLES$MAJORITY_VOTE <- as.factor(ENSEMBLES$MAJORITY_VOTE)
CM_ENSEMBLES <- confusionMatrix(data=ENSEMBLES$MAJORITY_VOTE, reference = dftest$churn, positive = '1')
CM_Function(CM_ENSEMBLES)

roc_score =roc(factor(dftest$churn, ordered=TRUE), factor(ENSEMBLES$MAJORITY_VOTE, ordered=TRUE))
auc <- round(auc(factor(dftest$churn, ordered=TRUE), factor(ENSEMBLES$MAJORITY_VOTE, ordered=TRUE)),4)
ggroc(roc_score, colour = '#0D8387', size = 1) +
ggtitle(paste0('ROC Curve ', '(AUC = ', auc, ')')) + theme_minimal() + theme(plot.title = element_text(face = "bold")) + labs(x="Specificity", y="Sensitivity")

ENSEMBLES - MAJORITY VOTING ON ORIGINAL
BOOSTING CTREE
BAGGING
ENSEMBLES <- cbind(PRED_BOOSTING_ORIGINAL,PRED_CTREE_ORIGINAL,PRED_BAGGING_ORIGINAL)
ENSEMBLES <- as.data.frame(ENSEMBLES)
ENSEMBLES <- ifelse(ENSEMBLES == 2, 1, 0)
MAJORITY_VOTE <- rep(0,nrow(ENSEMBLES))
MAJORITY_VOTE <- ifelse(rowSums(ENSEMBLES) > (ncol(ENSEMBLES)-1)/2, 1, 0)
ENSEMBLES <- cbind(ENSEMBLES,MAJORITY_VOTE)
ENSEMBLES <- as.data.frame(ENSEMBLES)
ENSEMBLES$MAJORITY_VOTE <- as.factor(ENSEMBLES$MAJORITY_VOTE)
CM_ENSEMBLES <- confusionMatrix(data=ENSEMBLES$MAJORITY_VOTE, reference = df_original_test$churn, positive = '1')
CM_Function(CM_ENSEMBLES)

roc_score =roc(factor(df_original_test$churn, ordered=TRUE), factor(ENSEMBLES$MAJORITY_VOTE, ordered=TRUE))
auc <- round(auc(factor(df_original_test$churn, ordered=TRUE), factor(ENSEMBLES$MAJORITY_VOTE, ordered=TRUE)),4)
ggroc(roc_score, colour = '#0D8387', size = 1) +
ggtitle(paste0('ROC Curve ', '(AUC = ', auc, ')')) + theme_minimal() + theme(plot.title = element_text(face = "bold")) + labs(x="Specificity", y="Sensitivity")

ENSEMBLES - MAJORITY VOTING
KNN CTREE
BAGGING
ENSEMBLES <- cbind(PRED_KNN,PRED_CTREE,PRED_BAGGING)
ENSEMBLES <- as.data.frame(ENSEMBLES)
ENSEMBLES <- ifelse(ENSEMBLES == 2, 1, 0)
MAJORITY_VOTE <- rep(0,nrow(ENSEMBLES))
MAJORITY_VOTE <- ifelse(rowSums(ENSEMBLES) > (ncol(ENSEMBLES)-1)/2, 1, 0)
ENSEMBLES <- cbind(ENSEMBLES,MAJORITY_VOTE)
ENSEMBLES <- as.data.frame(ENSEMBLES)
ENSEMBLES$MAJORITY_VOTE <- as.factor(ENSEMBLES$MAJORITY_VOTE)
CM_ENSEMBLES <- confusionMatrix(data=ENSEMBLES$MAJORITY_VOTE, reference = dftest$churn, positive = '1')
CM_Function(CM_ENSEMBLES)

roc_score =roc(factor(dftest$churn, ordered=TRUE), factor(ENSEMBLES$MAJORITY_VOTE, ordered=TRUE))
auc <- round(auc(factor(dftest$churn, ordered=TRUE), factor(ENSEMBLES$MAJORITY_VOTE, ordered=TRUE)),4)
ggroc(roc_score, colour = '#0D8387', size = 1) +
ggtitle(paste0('ROC Curve ', '(AUC = ', auc, ')')) + theme_minimal() + theme(plot.title = element_text(face = "bold")) + labs(x="Specificity", y="Sensitivity")

ENSEMBLES - MAJORITY VOTING ON ORIGINAL
KNN CTREE
BAGGING
ENSEMBLES <- cbind(PRED_KNN_ORIGINAL,PRED_CTREE_ORIGINAL,PRED_BAGGING_ORIGINAL)
ENSEMBLES <- as.data.frame(ENSEMBLES)
ENSEMBLES <- ifelse(ENSEMBLES == 2, 1, 0)
MAJORITY_VOTE <- rep(0,nrow(ENSEMBLES))
MAJORITY_VOTE <- ifelse(rowSums(ENSEMBLES) > (ncol(ENSEMBLES)-1)/2, 1, 0)
ENSEMBLES <- cbind(ENSEMBLES,MAJORITY_VOTE)
ENSEMBLES <- as.data.frame(ENSEMBLES)
ENSEMBLES$MAJORITY_VOTE <- as.factor(ENSEMBLES$MAJORITY_VOTE)
CM_ENSEMBLES <- confusionMatrix(data=ENSEMBLES$MAJORITY_VOTE, reference = df_original_test$churn, positive = '1')
CM_Function(CM_ENSEMBLES)

roc_score =roc(factor(df_original_test$churn, ordered=TRUE), factor(ENSEMBLES$MAJORITY_VOTE, ordered=TRUE))
auc <- round(auc(factor(df_original_test$churn, ordered=TRUE), factor(ENSEMBLES$MAJORITY_VOTE, ordered=TRUE)),4)
ggroc(roc_score, colour = '#0D8387', size = 1) +
ggtitle(paste0('ROC Curve ', '(AUC = ', auc, ')')) + theme_minimal() + theme(plot.title = element_text(face = "bold")) + labs(x="Specificity", y="Sensitivity")

PRESENTATION ASSETS
rm(list = ls())
# READ DATA
df <- readxl::read_xls('Cchurn.xls')
df$international_plan <- factor(df$international_plan, levels = c('no', 'yes'), labels = c('0','1'))
df$voice_mail_plan <- factor(df$voice_mail_plan, levels = c('no', 'yes'), labels = c('0','1'))
df$churn <- factor(df$churn, levels = c('no', 'yes'), labels = c('No','Yes'))
# DATA ENGINEERING
df$total_day_charge_per_minute <- ifelse(df$total_day_minutes == 0, 0, df$total_day_charge / df$total_day_minutes)
df$total_eve_charge_per_minute <- ifelse(df$total_eve_minutes == 0, 0, df$total_eve_charge / df$total_eve_minutes)
df$total_night_charge_per_minute <- ifelse(df$total_night_minutes == 0, 0, df$total_night_charge / df$total_night_minutes)
df$total_intl_charge_per_minute <- ifelse(df$total_intl_minutes == 0, 0, df$total_intl_charge / df$total_intl_minutes)
df <- subset(df, select = -c(total_day_charge, total_day_minutes, total_eve_charge, total_eve_minutes, total_night_charge, total_night_minutes, total_intl_charge, total_intl_minutes))
colnames(df) <- c("Account Length", "International Plan","Voice Mail Plan","Voice Mail Messages","Total Days Calls","Total Evening Calls","Total Night Calls","Total Internation Calls","Total Customer Service Call","Customer Churn","Total Day Charge/Minute", "Total Evening Charge/Minute","Total Night Charge/Minute","Total International Charge/Minute")
PAIRS PLOT
# Load the necessary libraries
library(ggplot2)
library(GGally)
library(ggthemes)
# Set the main color palette
colors <- c("#0D8387", "#870D27")
# Create the ggpair plot
PAIRS1 <- ggpairs(df,columns = c(1:4), mapping = aes(col = `Customer Churn`, alpha = 0.9)) + scale_color_manual(values = colors) + scale_fill_manual(values = colors) + labs(title = "Customer Telecommunication Data", subtitle = "Customer Churn = Yes is red", caption="From Variable 1 to 4") + theme(plot.title = element_text(face = "bold"))
PAIRS1

PAIRS2 <- ggpairs(df,columns = c(5:9), mapping = aes(col = `Customer Churn`, alpha = 0.9)) + scale_color_manual(values = colors) + scale_fill_manual(values = colors) + labs(title = "Customer Telecommunication Data", subtitle = "Customer Churn = Yes is red", caption="From Variable 5 to 9") + theme(plot.title = element_text(face = "bold"))
PAIRS2

PAIRS3 <- ggpairs(df,columns = c(10:10), mapping = aes(col = `Customer Churn`, alpha = 0.9)) + scale_color_manual(values = colors) + scale_fill_manual(values = colors) + labs(title = "Customer Telecommunication Data", subtitle = "", y="Count") + theme(plot.title = element_text(face = "bold")) + theme_minimal() + theme(plot.title = element_text(face = "bold")) + annotate("text", x = 2, y = 900, label = "14.14%", colour = "#870D27", size=8) + annotate("text", x = 1, y = 4500, label = "85.86%", colour = "#0D8387", size=8) + theme(axis.text.x=element_text(size=16))
PAIRS3

PAIRS4 <- ggpairs(df,columns = c(11:14), mapping = aes(col = `Customer Churn`, alpha = 0.9)) + scale_color_manual(values = colors) + scale_fill_manual(values = colors) + labs(title = "Customer Telecommunication Data", subtitle = "Customer Churn = Yes is red",caption="From Variable 11 to 14") + theme(plot.title = element_text(face = "bold"))
PAIRS4

df$`Customer Churn` <- factor(df$`Customer Churn`, levels = c('No', 'Yes'), labels = c(0,1))
df$`Customer Churn` <- as.integer(df$`Customer Churn`)
df$`Customer Churn` <- df$`Customer Churn` -1
Proportions_Churn <- sum(df$`Customer Churn`[df$`Customer Churn` == 1])/nrow(df)
Proportions_No_Churn <- 1-Proportions_Churn
Proportions of Customer who churned => 14.14% Versus 85.86% who
didn’t churn.